This application claims priority from German Application No. 10021518.1 filed on May 3, 2000.
The invention relates to a valve arrangement comprising a plurality of valve units which on mutually opposite sides have a respective mounting face and which for forming a subassembly are arranged in an array direction one after the other and with facing mounting faces turned toward each other side by side, each valve unit containing at least one internal fluid duct extending athwart the array direction.
A valve arrangement of this type is for example disclosed in the European patent publication 0 678 676 B1. It comprises a plurality of tabular valve units, which are clamped together by ties as a subassembly, adjacent valve units resting against each other at mutually facing mounting faces. Each valve unit comprises a valve means able to control the fluid flow in the power ducts which open at an outer face, aligned athwart the array direction of the valve units. The supply of fluid and escape thereof as regards the valve units is by way of fluid ducts, which extend through the individual valve units in the array direction and are aligned with each other.
As part of attempts to miniaturize the prior art valve arrangement it has been found that in the array direction a certain minimum size can not be gone below if the desired fluid cross sections are to be ensured.
Accordingly one object of the present invention is to create a valve arrangement of the type initially mentioned which may be designed with smaller overall sizes without impairing functionality.
In order to achieve this object there is a provision such that at least one of the internal flow ducts is delimited on a first longitudinal side, which faces the first mounting face, by a lateral duct wall of the respective valve unit and on its second longitudinal side, which faces the other, second mounting side, is open along a length section extending at least for part of its length, the open length section being covered by the lateral duct wall of the adjacent valve unit mounted on the second mounting side.
This means that flow ducts having a larger width than in the prior art may be produced extending in the interior of the valve units athwart the array direction. Only one of the two duct walls delimiting the respective flow duct at the mounting sides on the longitudinal side is a direct component of the valve unit containing the flow duct. The opposite duct wall is on the other hand constituted at least partially by the mounted adjacent valve unit so that the flow duct may extend within the associated valve unit on a longitudinal side as regards its width as far as the next mounted valve unit. It is in this manner that the overall width of the valve units may be reduced without impairing the flow cross section of the respective internal flow duct. A further advantage resulting from this special-purpose design structure is that even relatively complicated, non-linear internal flow ducts may be produce extremely simply, since such flow ducts may be formed from the corresponding mounting side as groove-like recesses, for example in the case of casting the respective components of the valve units.
For example the German patent publication 4,324,939 C2 and the European patent publication 0 643 811 B1 have already disclosed providing valve units with a longitudinally divided housing, which in the parting plane has groove-like recesses, which in the assembled state of the housing compliment each other to form flow ducts. There is in this case however no interaction such that a valve housing at the same time performs a housing function as regards the adjacent valve unit. As disclosed in the U.S. Pat. No. 5,341,846 even in the case of valve units having longitudinally split housings designers adhered to a individual conventional array, even when it was a question of collecting a plurality of valve units together as a valve arrangement in a subassembly.
Further advantageous developments of the invention are defined in the dependent claims.
At least one internal flow duct having an open length section preferably constitutes a power duct in the respective valve unit, which, starting at one valve means extends to an outer face of the valve unit running athwart the array direction, where connection means are associated with it, which render possible the connection of a fluid line leading to a load. The open length section may moreover extend along the entire duct length or only a part of the respective flow duct, independently of the type of associated flow duct. In this connection at least one internal flow duct may possess, following its open length section, a peripherally completely closed length section, by way of which for example the connection of a fluid duct leading to other equipment is possible directly or indirectly. Since the flow duct is completely closed adjacent to connection opening peripherally, it is possible to readily provide a sealed connection to further duct or line means leading to further equipment.
In the case of a particularly convenient design of the valve arrangement the valve units respectively have a main body, which is fitted with a valve means and wherein the at least one internal flow duct having an open length section extends. The valve means is in this case preferably integrated in the main body.
Particularly compact dimensions may be ensured if the valve units respectively have a tabular or plate-like configuration.
In the array direction each valve unit can have one or more fluid ducts extending through it, which respectively communicate on the one hand with a valve means of the respective valve unit and on the other hand communicate with corresponding fluid ducts of the respectively adjacent valve unit in order to create a fluid connection extending through all valve units, such fluid connection rendering possible a common supply and removal of the pressure medium necessary for operation.
Between adjacent valve units it is convenient to provide sealing means, which in the peripheral region of the mutually communicating openings of the fluid ducts and in the peripheral region of the open length section of the at least one internal flow duct are responsible for a hermetic sealing action between adjacent valve units. These sealing means may for instance be constituted by a uniform sealing element placed between adjacent valve units.
By having interlocking centering means on adjacent valve units assembly with the desired relative position of the valve units may be facilitated.
It is furthermore expedient for the first mounting face associated with the lateral duct wall the valve units to be an even smooth surface, something rendering possible extremely simple manufacture. To the extent that groove-like recesses are necessary to accommodate sealing means, such recesses will be preferably on the second mounting face of the respective valve unit for which the open length section or sections of one or more internal flow ducts are provided.